Generally, an electric guitar needs no or a small inner resonance space for natural amplification of string vibration, compared with an acoustic guitar such a classic guitar, a flamenco guitar, and a folk guitar. Accordingly, a degree of freedom of a form and a design is large, and products of electric guitars having various shapes and forms are designed and on the market.
However, concerning a basic configuration of an electric guitar, two types of models illustrated in FIG. 7 and FIG. 8 are representatively standard.
The electric guitar illustrated in FIG. 7 is a type (referred to as “Gibson (registered trademark)” type in the following) of which the product name is the “Les Paul (registered trademark)” model announced by Gibson (registered trademark) Guitar Corporation in 1952. The electric guitar illustrated in FIG. 8 is a type (referred to as “Fender (registered trademark)” type in the following) of which the product name is the “Stratocaster (registered trademark)” model announced by Fender (registered trademark) Musical Instruments Corporation in 1954.
These two types are used by quite a number of prominent musicians and are the most famous models in the world. Ninety percent or more of electric guitars on the market have basic configurations that are the same as the configurations of these two types of models or that are derivatives of a configuration or combination of these two types of models.
Beginning from these two representative types of models, substantially all electric guitars are each provided with a plurality of electromagnetic pickups.
For example, two electromagnetic pickups are mounted in a main body 2 of the Gibson type of electric guitar 1 illustrated in FIG. 7. The pickup mounted at the end of a neck 3 is called a front pickup 4, and the pickup mounted at the bridge 5 is called a rear pickup 6.
The front pickup 4 and rear pickup 6 are each attached to the main body 2 via a pickup mounting frame body called an escutcheon 7.
Another configuration of the Gibson type of electric guitar 1 is as follows.
The electric guitar 1 includes strings 8, a tail piece 9, a pickup selecting switch 10, control knobs 11, an output jack 12, a pickguard 13, and strap pins 14. Each of the strings 8 are held by a string tuning peg (not illustrated) at a distal end of the neck 3, and passes over the bridge 5 such that the other ends of the strings 8 are held by the tail piece 9. The control knobs 11 can control volume and sound quality (tone).
In the case of the Fender type of electric guitar 15 illustrated in FIG. 8, three electromagnetic pickups are mounted. The pickup mounted at the neck 3 is called a front pickup 16, the pickup mounted at the bridge 17 is called a rear pickup 18, and the pickup mounted in the middle is called a center (or middle) pickup 19.
The front pickup 16, rear pickup 18, and center pickup 19 are attached to the main body 2 via a pickguard 20 formed of a plastic plate or an aluminum plate.
General electric guitars have the above-described configurations. Particularly, a combination of front pickup 4 and rear pickup 6, or front pickup 16, rear pickup 18, and center pickup 19 are mounted to have an important role in musical expression.
The front pickup 4, 16 is attached close to the neck 3. Accordingly, string vibration detected by the front pickup 4, 16 includes a large fundamental tone component and relatively small harmonic overtones so that its tone has a soft and warm sound characteristic.
The rear pickup 6, 18 is attached close to the bridge 5, 17. Accordingly, string vibration detected by the rear pickup 6, 18 includes a smaller fundamental tone component and relatively large harmonic overtones so that its tone has a hard, sharp, and bright sound characteristic.
The center pickup 19 of the latter type has a sound characteristics intermediate between those of the front pickup 16 and the rear pickup 18.
Mounted in the electric guitar 1, 15 is a pickup selecting switch 10 that makes switching between the front pickup 4 and the rear pickup 6, or among the front pickup 16, the rear pickup 18, and the center pickup 19 possible. In the pickup selecting switch 10, two or more out of the front pickup 4, 16, the rear pickup 6, 18, and the center pickup 19 can be simultaneously turned on so that combined sound characteristics can be obtained, as well.
Thus, the electric guitar 1, 15 includes a combination of the mounted front pickup 4 and rear pickup 6, or the mounted front pickup 16, rear pickup 18, and center pickup 19, and includes the selecting mechanism. Accordingly, a musician can play by selecting the pickup in accordance with sound characteristics necessary for expressing his or her own music.
A musician often plays while changing sounds even in single tune by using the front pickup 4, 16 with a soft and warmer sound characteristic at the time of playing a rhythm, and using the rear pickup 6, 18 with a hard and sharp sound characteristic at the time of playing a lead (melody or improvisation), for example.
In other words, in such an electric guitar, it is an essential to mount a plurality of pickups as structural elements.
Generally, an electric guitar has the characteristic that string vibration becomes maximum at the time of picking (or plucking), and then attenuates.
This is the greatest characteristic of what is called a plucked string instrument, i.e., a group of musical instruments to which a guitar belongs. Recently, a string vibration sustaining device that makes string vibration last permanently by electromagnetic energy has been proposed, and has been favorably reviewed in that new expression can be created in an electric guitar.
This string vibration sustaining device has been put on the market by the present applicant with the product name of “FERNANDES SUSTAINER (registered trademark)”. In addition, another string vibration sustaining device has been put on the market by Mr. Alan Hoover in America with the product name of “SUSTAINIAC”. Further, in the past, a string vibration sustaining device was put on the market by Mr. Floyd Rose in America with the product name of “Floyd Rose•SUSTAINER”.
The techniques of the string vibration sustaining devices of these three parties are disclosed in U.S. Pat. No. 4,852,444 (Alan A. Hoover et al.) (referred to as “document 1” in the following), International Patent Application Publication No. WO90/13888 (Alan A. Hoover et al.) (referred to as “document 2” in the following), International Patent Application Publication No. WO89/11717 (Floyd D. Rose et al.) (referred to as “document 3” in the following), U.S. Pat. No. 5,292,999 (Fernandes (registered trademark) Co., Ltd) (referred to as “document 4” in the following), and U.S. Pat. No. 5,585,588 (Fernandes (registered trademark) Co., Ltd) (referred to as “document 5” in the following).
The string vibration sustaining devices disclosed in the documents 1 to 5 basically have the following configuration.
The string vibration sustaining device is constituted by a rear pickup that detects a frequency of string vibration and converts the detected frequency of string vibration into an electrical signal, an amplifier that amplifies the converted electrical signal, and an electromagnetic driver that converts the amplified electrical signal into a magnetic signal to excite strings.
The electromagnetic driver in such a conventional string vibration sustaining device is desirably mounted near the neck since it is dynamically difficult to excite strings near the bridge because of the configuration of an electric guitar for giving sufficient exciting force to the strings. In other words, the electromagnetic driver is required to be mounted at the position where the strings are most easily excited, i.e. where the front pickup was originally arranged.
This leads to a serious difficulty for the electric guitar in that the front pickup which is indispensable for the electric guitar as described above cannot be mounted near the neck of the electric guitar, and musical expression of the front pickup is spoiled.
To overcome this difficulty, as disclosed in the document 2 by the above-mentioned Mr. Alan Hoover, there is proposed a technique of using the electromagnetic driver as the front pickup when the electromagnetic driver is not used as the exciting device.
The electromagnetic driver basically has a configuration similar to that of the pickup. However, for exciting the strings, a winding number and a wire diameter of a coil of the electromagnetic driver are different from those of the pickup. For this reason, when the electromagnetic driver is used as it is to function as the front pickup, a detected signal is weak. In view of this, according to the technique of the document 2, the detected signal is amplified up to a level of a signal of the pickup by one or both of a boosting transformer and an operational amplifier.
In this way, a sound characteristic approximately similar to that of the front pickup can be obtained. However, there is a problem in that the signal is inevitably processed by the operational amplifier and an internal circuit of the string vibration sustaining device, resulting in an actively operating pickup, and for this reason, the signal becomes largely deviated from the exact original signal of the front pickup.
As described above, the electromagnetic driver and the pickup basically use coils of which wire diameters and winding numbers are different from each other. Accordingly, even when amplification and boosting is appropriately performed, it is difficult to obtain a fundamental sound characteristic of the front pickup.
Meanwhile, since the front pickup inevitably becomes an actively operating pickup as described above, there is a difficulty in that electric power needs to be supplied by a battery for operating the amplifier even when the string vibration sustaining device itself is not used, and when the battery is used up, a sound signal cannot be output at all.
From a different standpoint of suppressing magnetic feedback that is the most difficult problem in this type of string vibration sustaining device, it is necessary to arrange the electromagnetic driver and the rear pickup as far apart from each other as possible.
In other words, since the electromagnetic driver radiates strong magnetic energy while performing excitation, a part of the magnetic energy enters the rear pickup, and as a result, oscillation is caused to output an unnecessary noise other than an original musical signal of a musical instrument.
As a technique for suppressing such magnetic feedback, a string vibration sustaining device adopting “a magnetic un-equilibrium device (shunt plate)” disclosed in the document 2 by the above-mentioned Mr. Alan Hoover was developed. “Horizontal structure drivers” disclosed in the documents 4 and 5 by the present applicant were developed as well.
These techniques effectively enable practical implementation of a string vibration sustaining device. To suppress the magnetic feedback most ideally and theoretically, it was necessary to arrange the electromagnetic driver and the rear pickup as far apart from each other as possible. However, in a string vibration sustaining device in which the electromagnetic driver is arranged at the conventional position of the front pickup, greater separation than at present is impossible.